STIGEOCLONIUM. Ill 



Dr. Kirehner suggests the following division of the many 

 varieties of this species. 



a. genuinum, Kirch. Secondary branchlets sparse, short, 

 subulate, upright, about two inches long. 



b. lubricum, Rab. Stems decidedly thicker than the pri- 

 mary branches; secondary branchlets numerous, 

 close, short, subulate. 



c. uniforme, Kab. Chlorophyl scattered, stems and branches 

 similar; secondary branchlets slender and long, 

 attached about the middle of the cell. Filaments 

 i-f inch long. 



d. irregulare, Rab. Filaments often more or less flattened 

 in process of development ; they divide longitudi- 

 nally. 



e. bulbiferum, Wolle. We add this as a peculiar form with 

 large oval oogonium-like cells at the base of the 

 forked stems. Are they sporangia f 



Syn. Draparnaldia tennis, Hass. ; Conferva lubrica, Dillw. 



Found everywhere in one or another form, most frequently 

 in rapicMy flowing waters, in midwinter as well as during the 

 summer months. 



Plate XOVI, fig. 6, a large sporangium as occurring fre- 

 quently in cultivation of this plant ; figs. 7, 8, 9, clusters of 

 microzoospores come to rest and developing young plants ; 

 fig. 12, var. bulbiferum ; figs. 13-16 representing the sporan- 

 gium-like cells. 



Plate CI, figs. 5, 6, 7, three plants, var. irregulare ; show 

 the proliferation of the cells of filaments. 



Plate CI, figs. 8, 9, var. uniforme, forma gracile, Kg., 

 "basal articulations about three times as long as wide; 

 branches sometimes cuspidate, torulose;" figs. 10, 11, 12, 

 cells of filaments developing sporangia. 



STIGEOCLONIUM THERMALE, A. Br. 



Bright green, affects waters of high temperature ; one to 

 two inches long, very much branched in a fasciculate man- 

 ner; filaments and branches attenuated upward to a cuspi- 

 date apex ; branches mostly alternate, rather remote, erect 

 patent ; articulations equal, or twice as long as wide at the 

 base, longer above. 



Diameter of cells of filaments, 7-10 /* ; 2-5 times longer. 



Thermal springs ; in flumes of hot waste water from steam 

 engines, etc. 



